Streams Geo-Morphology

Summary

Abstract:

In 1994, 16 stream transects were established in the McMurdo Dry Valleys of Antarctica 63 beginning a long term data set characterizing microbial communities and channel geometry. The 64 transects were established to record microbial mat dynamics and stream geomorphology. To accomplish this, the transects were surveyed for points of interest outside and inside the stream channel. Beginning in 2010 the microbial surveys received ground based LiDAR support. This allowed for greater resolution in mapping and analyzing stream morphology than traditional surveying methods. Using surveyed microbial mats as an indicator of a location in time, a history of channel elevations was created for 7 transects. Here, you will find the massive long term data for the geomorphology of seven of the streams, along with detailed references to the methodology and results and other findings published in Steven Crisp thesis dissertation.

iv. Next to the Vectorization Menu, select “Vectorization Trace” Tool.

v. Click on beginning of Contour Line, and allow arrow to trace line automatically

1. Sometimes at intersections or other unnatural features, the line stops. “Jump” Over the break with “s” and continue on with line

2. Double Click or press F2 to end Vector trace

3. Arc loves to not work after crossing a line. It jumps giant gaps to connect with completely unrelated lines although it should follow the line indicated. Need to contact Arc about this, or just finish the contour manually.

4. If there are large gaps in the contour lines, manually change the classification scheme to account for gray areas to be black and not white.

vi. ArcScan allows for automation of contours, but I don’t believe this works very well. Instructions in website or pdf above

vii. Once line is created, go into Attribute Table of shapefile and add elevation of contour line just created

1. Check BM elevation from Alger

2. Check BM elevation from UNAVCO

3. +/- difference from the two for each contour elevation

viii. Repeat for all contour lines

ix. “Stop Editing

x. Save Map Frequently as ex. “XX.mxd”

III. Topo to raster 3D analyst for now? Spatial does stream polyline better(Not using this anymore)

Research Section:

Keywords:

This material is based upon work supported by the National Science Foundation Grant #OPP-1637708 for Long Term Ecological Research. Any opinions, findings, conclusions, or recommendations expressed here are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.